1. Field of the Invention
The present invention relates to a sliding structure for an electronic device, and more particularly, to a low friction and stable sliding structure for an electronic device, such as a telephone, to enable the electronic device to have reduced thickness.
2. Description of the Related Art
As sliding structures have the advantages of simple handling and attractive design, they are largely used in portable electronic devices such as cellular phones, cameras, portable multimedia players (PMP), personal computer (PC) or the like. FIG. 1A is a schematic perspective view illustrating a conventional cellular phone 10, and FIG. 1B is a schematic side view illustrating the conventional cellular phone 10 of FIG. 1A and its sliding structure 40.
Referring to FIGS. 1A and 1B, the conventional cellular phone 10 having the sliding structure 40 further includes a receiver portion 20 including a displaying portion 2, and a transmitter portion 30 including an operation-key portion 3, such as number key buttons or the like. In order to use the conventional cellular phone 10, the receiver portion 20 is pushed up via the sliding structure 40.
Referring to FIG. 1B, the conventional sliding structure 40 is disclosed in Korean Patent Publication No. 10-2005-0037649 and includes a first sliding member 41 and a second sliding member 42 that slides along the first sliding member 41. The first sliding member 41 includes a first magnet 43 and the second sliding member 42 includes a pair of second magnets 44a and 44b, and thus a sliding operation is assisted by a magnetic force.
In the conventional sliding structure 40, friction between the first sliding member 41 and the second sliding member 42 impedes the sliding operation. In particular, friction between the first sliding member 41 and the second sliding member 42 increases during a sliding operation due to an attractive force between the first magnet 43 and the pair of second magnets 44a and 44b. Accordingly, a user may need to push the sliding structure 40 harder in order to operate the conventional cellular phone 10.
FIG. 1C is a cross-sectional view illustrating another conventional sliding structure 50. Referring to FIG. 1C, the sliding structure 50, disclosed in Korean Patent Publication No. 10-2005-0089584, includes a first sliding member 51 and a second sliding member 52 sliding on the first sliding member 51.
The first sliding member 51 includes a first magnet 53 having a horseshoe shape, and the second sliding member 52 includes a second magnet 54 also having a horseshoe shape. The first magnet 53 and the second magnet 54 are alternately arranged to facilitate a sliding operation.
In the sliding structure 50, repulsive forces act between the N pole of the first magnet 53 and the N pole of the second magnet 54, and between the S pole of the first magnet 53 and the S pole of the second magnet 54 when a sliding operation is being performed. Simultaneously, an attractive force also acts between the S pole of the first magnet 53 and the N pole of the second magnet 54. Accordingly, the sliding operation does not proceed smoothly since a user may need to push the sliding structure 50 harder due to the attractive force between the first magnet 53 and the second magnet 54.
In addition, in the sliding structure 50, since the first magnet 53 and the second magnet 54, which have horseshoe shapes, are alternately arranged, a large space for such an arrangement is required, and thus the thickness of the sliding structure 50 is increased. Also, in curved parts where parts of the first magnetic member 53 and the second magnetic member 54 do not overlap, since a repulsive force between the parts of the first magnetic member 53 and the second magnetic member 54 is reduced, the sliding operation cannot be easily performed.
Another example of a conventional sliding structure is a sliding structure that can slide in four directions. The sliding structure includes a first sliding member and a second sliding member, which can slide in a vertical direction, and a third sliding member and a fourth sliding member, which can slide in a horizontal direction. However, in such a conventional four-directional sliding structure, since two magnetic levitation modules are disposed perpendicular or substantially perpendicular to each other, the thickness of the sliding structure is increased.
Generally, in the conventional four-directional sliding structure, an extension key pad is formed in a vertical direction on the second sliding member that slides in a vertical direction, and a number key pad is formed in a horizontal direction on the third sliding member that slides in a horizontal direction. In this arrangement, since the readable display directions, which are directions in which a user can read key pads without having to rotate a structure, of the extension key pad and the number key pad are perpendicular or substantially perpendicular to each other, a user has to read the number key pad in a perpendicular or substantially perpendicular direction to the extension key pad when both the number key pad and the extension key pad are being used.